aod 9604

HGH fragment. went to phase 2b for obesity. failed. the data says it doesn't work.

tier D · weight loss · frag 176-191 phase 2b · failed

verdict

HGH fragment. went to phase 2b for obesity. failed. the data says it doesn't work for the marketed indication.

if you're asking whether AOD-9604 produces meaningful fat loss — no, on the rigorous evidence. phase 2 trials confirmed the lipolysis-without-IGF-1 selectivity cleanly. phase 2b weight-loss endpoints did not reach clinical-meaningfulness thresholds, which is why Metabolic Pharmaceuticals shelved the program. then semaglutide arrived with 15% body weight loss and tirzepatide with 20-25%. an order of magnitude bigger effect through a completely different mechanism. the compound does what it was designed to do, just at a magnitude that doesn't matter for obesity.

if you're asking about the GRAS / 'FDA-cleared' marketing — GRAS (2014) means safe as a supplement ingredient, not effective for weight loss. it gets routinely misrepresented in supplement marketing as 'FDA-cleared.' the Dec 4, 2024 FDA PCAC voted against adding AOD-9604 to the 503A bulks list, so compounding pharmacies cannot legally produce it either. research-peptide vendors continue because weak evidence still sells.

if you came in via the 'GH fat-burning without IGF-1' framing — the selectivity claim is real. the safety record is genuinely tame. the magnitude of the lipolytic effect is what failed the trial. AOD-9604 is the best-studied compound in the HGH-fragment class and the data says it was tested honestly and lost. that's a cleaner verdict than most peptides at this tier.

based on published evidence and disclosed clinical practice. not medical advice.

why D-tier

D-tier because the compound has the best human clinical data in its class and the data shows it doesn't work meaningfully for weight loss. Not F-tier because the compound is real, safe, and does what it claims pharmacologically (isolated lipolytic activity without broader GH effects). The problem is that the magnitude is too small to matter. This is the honest tier for 'we tested it properly and it failed.' It's more respectful than F-tier and more accurate than C-tier. The GLP-1 revolution has made the entire premise obsolete regardless.

the core tension

AOD-9604 is HGH Frag 176-191's developed sibling, same C-terminal GH sequence, with an N-terminal tyrosine added for improved stability and manufacturability. Metabolic Pharmaceuticals took this specific compound through phase 1 and phase 2 clinical trials for obesity. The trials ran. The safety profile came back clean. The efficacy profile came back underwhelming, modest weight loss not clinically meaningful, not enough to progress to phase 3. Metabolic Pharmaceuticals discontinued the obesity program around 2007. The compound later received GRAS-style ingredient-safety positioning, which is not drug approval and not weight-loss efficacy clearance. The honest tier position: this is the compound in the HGH fragment class with the best human data, and the best human data says it doesn't work.

what it is

AOD9604 is the Tyr-modified hGH 176-191 analog, a 16-amino-acid peptide designed to isolate GH's lipolytic activity without IGF-1 elevation, hyperglycemia, or the broader anabolic side effect set. A modified sibling of HGH Frag 176-191.

what it does

aod9604 increases lipolytic markers without raising IGF-1 or causing hyperglycemia. Phase 2 trials confirmed the selectivity claim cleanly. Modest fat-mobilization effects are detectable; clinically meaningful weight loss is not. The compound does exactly what it was designed to do, just at a magnitude that doesn't matter for obesity treatment.

origin

developed by Metabolic Pharmaceuticals, an Australian biotech, through a full pharmaceutical clinical program. Phase 1 safety passed, phase 2a confirmed lipolytic markers, phase 2b efficacy failed in 2007. The obesity program was discontinued. AOD-9604 has a GRAS food-ingredient safety record, not FDA drug approval, not weight-loss efficacy clearance, and not a 503A compounding green light.

why researchers are interested

selective lipolysis without IGF-1 effects is mechanistically clean and theoretically appealing. The clinical trial paper trail makes the compound feel more legitimate than most research peptides. GRAS status gets routinely misrepresented in supplement marketing as 'FDA-cleared,' which sells. Side effect profile is genuinely tame.

does it work

this is the best-studied compound in the HGH-fragment class, and the data says no. Phase 2b weight-loss endpoints didn't reach clinical-meaningfulness thresholds, which is why Metabolic Pharmaceuticals shelved the program. Then semaglutide arrived with 15% body weight loss, and tirzepatide with 20-25%, an order of magnitude bigger effect through a completely different mechanism. AOD-9604's safety record is cleaner than its efficacy record. It was tested honestly and lost. GRAS (2014) means safe as a supplement ingredient, not effective for weight loss. The Dec 4, 2024 FDA PCAC voted against adding it to the 503A bulks list, so compounding pharmacies cannot legally produce it either. Research-peptide vendors continue because weak evidence still sells.

claims vs the data

• produces selective lipolysis without affecting IGF-1 — supported — Phase 1 and 2 trials confirmed the selectivity claim, AOD-9604 increases lipolytic markers without elevating IGF-1 or causing hyperglycemia. The pharmacology is real and was the theoretical appeal.
• produces clinically meaningful weight loss — contradicted — This is the specific claim the phase 2b trials tested and rejected. Effect sizes were statistically detectable but not clinically meaningful, the basis for Metabolic Pharmaceuticals discontinuing the obesity program.
• FDA-approved for weight loss — contradicted — Direct factual error. AOD-9604 has GRAS status (Generally Recognized As Safe) for dietary supplement ingredient use. That is not drug approval. It certifies safety, not efficacy, and does not authorize weight-loss marketing claims.
• clean safety record in the published human program — supported — The safety profile was clean across the published human trial program. That supports ingredient-safety context, not a therapeutic weight-loss claim.
• competitive with modern weight-loss drugs — overreach — Semaglutide produces 15-20% body weight loss; tirzepatide 20-25%. AOD-9604 trials showed single-digit-percentage effects that didn't reach phase 3 thresholds. Not in the same category.
• AOD-9604 failed because nobody studied it properly — contradicted — This is one of the rare gray-market fat-loss peptides that actually did get a human development program. The safety profile looked relatively clean, but efficacy was not clinically meaningful enough to survive the obesity-drug market.

key facts

• molecular formula: C78H123N23O23S2
• molecular weight: 1815.1 Da
• amino acids: 16
• half-life: plasma half-life extended versus unmodified fragment; lipolytic effects acute and dose-dependent
• type: modified C-terminal hexadecapeptide of hGH (Tyr-stabilized hGH 176-191 analog)
• CAS: 221231-10-3
• phase 2b stage at which it formally failed
• 2007 year the obesity program was discontinued
• 2014 year of FDA GRAS status (supplement, not drug)
• ~15% body weight loss from semaglutide, for comparison

frequently asked questions

What is AOD-9604?

AOD-9604 is a modified version of the HGH Frag 176-191 C-terminal peptide, developed by Metabolic Pharmaceuticals as a potential obesity drug. It went through Phase 1 and Phase 2 clinical trials for weight loss before the program was discontinued.

What does AOD-9604 do?

AOD-9604 was designed to isolate growth hormone's lipolytic activity without the IGF-1 elevation or glucose effects of full HGH. Phase 2 clinical trials confirmed the selectivity, no IGF-1 changes, no hyperglycemia, but showed weight loss effects that were statistically detectable but clinically modest, leading to program discontinuation for the obesity indication. More recent research has explored the molecule in intra-articular osteoarthritis applications.

How is AOD-9604 typically administered?

Community injection protocols do not match the published human record. The published human safety study used oral dosing, and the obesity program failed on effect size. There is no FDA-approved dosing protocol.

What are the side effects of AOD-9604?

The published oral human safety study reported clean tolerability. Community injection use adds route-specific uncertainty that the published human record does not directly cover. The safety profile was good enough to support GRAS-style ingredient-safety positioning; the clinical failure was about effect size, not safety.

Is AOD-9604 FDA approved?

No as a drug. AOD-9604 has a GRAS safety determination for intended ingredient use, not an efficacy approval for weight loss. It is not FDA-approved for any therapeutic indication.

How much does AOD-9604 cost?

No clinical retail price. On the research-chemical market it is inexpensive. Supplement products containing AOD-9604 under the GRAS classification have variable pricing.

related peptides

• hgh frag 176-191 — the unmodified parent fragment, same class, less clinical data
• semaglutide — modern weight-loss comparator that obsoletes the whole premise
• hgh — the parent protein, very different effect profile

reptides grades the research record and cites the literature behind every call. research reference only; not medical advice.